多行正则表达式应在文件中多次匹配（如果可能，使用单行命令）答案

【问题标题】：Multi-line regex should match multiple times in a file (one-line command if possible)多行正则表达式应在文件中多次匹配（如果可能，使用单行命令）
【发布时间】：2018-12-13 14:59:02
【问题描述】：

我正在尝试将一些（多行）git 历史信息（提取文件名更改）转换为 CSV 文件。这是我的regex and sample file。它在该网站上运行良好。

正则表达式：

commit (.+)\n(?:.*\n)+?similarity index (\d+)+%\n(rename|copy) from (.+)\n\3 to (.+)\n

示例输入：

commit 2701af4b3b66340644b01835a03bcc760e1606f8
Author: ostrovsky.alex <ostrovsky.alex@a51b5712-02d0-11de-9992-cbdf800730d7>
Date:   Sat Oct 16 20:44:32 2010 +0000

    * Moved old sources to Maven src/main/java

diff --git a/alexo-chess/src/ao/chess/v2/move/Pawns.java b/alexo-chess/src/main/java/ao/chess/v2/move/Pawns.java
similarity index 100%
rename from alexo-chess/src/ao/chess/v2/move/Pawns.java
rename to alexo-chess/src/main/java/ao/chess/v2/move/Pawns.java

commit ea53898dcc969286078700f42ca5be36789e7ea7
Author: ostrovsky.alex <ostrovsky.alex@a51b5712-02d0-11de-9992-cbdf800730d7>
Date:   Sat Oct 17 03:30:43 2009 +0000

    synch

diff --git a/src/chess/v2/move/Pawns.java b/alexo-chess/src/ao/chess/v2/move/Pawns.java
similarity index 100%
copy from src/chess/v2/move/Pawns.java
copy to alexo-chess/src/ao/chess/v2/move/Pawns.java

commit b869f395429a2c1345ce100953bfc6038d9835f5
Author: ostrovsky.alex <ostrovsky.alex@a51b5712-02d0-11de-9992-cbdf800730d7>
Date:   Wed Oct 7 22:43:06 2009 +0000

    MctsPlayer works

diff --git a/ao/chess/v2/move/Pawns.java b/src/chess/v2/move/Pawns.java
similarity index 100%
copy from ao/chess/v2/move/Pawns.java
copy to src/chess/v2/move/Pawns.java

commit 4c697c510f5154d20be7500be1cbdecbaf99495c
Author: ostrovsky.alex <ostrovsky.alex@a51b5712-02d0-11de-9992-cbdf800730d7>
Date:   Wed Sep 23 15:06:17 2009 +0000

    * synch

diff --git a/v2/move/Pawns.java b/ao/chess/v2/move/Pawns.java
similarity index 95%
rename from v2/move/Pawns.java
rename to ao/chess/v2/move/Pawns.java
index e0172a3..e3659c5 100644
--- a/v2/move/Pawns.java
+++ b/ao/chess/v2/move/Pawns.java

但是，当我尝试运行以下 perl 命令（在 Windows 10 上的 git bash 中）时，我只得到一个匹配的行（与您可以在我链接的网站上看到的示例中的 4 行相反上）。

我知道这可能很愚蠢，就像它需要循环一样。但我对啜饮-0777 并多次应用模式感到困惑。我尝试了-p 选项，但它会打印出整个输入，我只想查看print 的输出（即CSV 行）。我还认为/g 会使该模式多次应用于输入文件，但由于-0777 将其全部设为一行，我不确定了。

<Pawns.java.history.txt perl -0777 -ne 'if (/commit (.+)\n(?:.*\n)+?similarity index (\d+)+%\n(rename|copy) from (.+)\n\3 to (.+)\n/g) { print $1.",".$2.",".$3.",".$4.",".$5."\n" }'

输出只有一行，而sample file一共应该是4行：

2701af4b3b66340644b01835a03bcc760e1606f8,100,rename,alexo-chess/src/ao/chess/v2/move/Pawns.java,alexo-chess/src/main/java/ao/chess/v2/move/Pawns.java

预期输出：

2701af4b3b66340644b01835a03bcc760e1606f8,100,rename,alexo-chess/src/ao/chess/v2/move/Pawns.java,alexo-chess/src/main/java/ao/chess/v2/move/Pawns.java
ea53898dcc969286078700f42ca5be36789e7ea7,100,copy,src/chess/v2/move/Pawns.java,alexo-chess/src/ao/chess/v2/move/Pawns.java
b869f395429a2c1345ce100953bfc6038d9835f5,100,copy,ao/chess/v2/move/Pawns.java,src/chess/v2/move/Pawns.java
4c697c510f5154d20be7500be1cbdecbaf99495c,95,rename,v2/move/Pawns.java,ao/chess/v2/move/Pawns.java

【问题讨论】：

@oguzismail 完成 - 感谢您的评论。

标签： regex bash git perl

【解决方案1】：

您只需将if 转换为while：

perl -0777 -ne 'while (/commit (.+)\n(?:.*\n)+?similarity index (\d+)+%\n(rename|copy) from (.+)\n\3 to (.+)\n/g) { print $1.",".$2.",".$3.",".$4.",".$5."\n" }' file

2701af4b3b66340644b01835a03bcc760e1606f8,100,rename,alexo-chess/src/ao/chess/v2/move/Pawns.java,alexo-chess/src/main/java/ao/chess/v2/move/Pawns.java
ea53898dcc969286078700f42ca5be36789e7ea7,100,copy,src/chess/v2/move/Pawns.java,alexo-chess/src/ao/chess/v2/move/Pawns.java
b869f395429a2c1345ce100953bfc6038d9835f5,100,copy,ao/chess/v2/move/Pawns.java,src/chess/v2/move/Pawns.java
4c697c510f5154d20be7500be1cbdecbaf99495c,95,rename,v2/move/Pawns.java,ao/chess/v2/move/Pawns.java

【讨论】：

【解决方案2】：

//g 运算符在列表上下文中返回捕获的结果。由于有 5 组捕获括号和 4 个匹配项，因此返回的列表有 20 个元素。您需要遍历该列表。您的代码只查看第一个匹配项。这是一种技术：

perl -0777 -nE '
    @matches = /commit (.+)\n(?:.*\n)+?similarity index (\d+)+%\n(rename|copy) from (.+)\n\3 to (.+)\n/g;
    $" = ",";
    while (@matches) {
        @thismatch = splice @matches, 0, 5;
        say "@thismatch";
    }
' Pawns.java.history.txt

【讨论】：